Download Lecture 4: Classical Conditioning in Humans 1/ Watson and Little

Lecture 4: Classical Conditioning in Humans
1/ Watson and Little Albert
2/ Classical conditioning and treatment of phobias
3/ Aversion therapy
4/ Classical conditioning and Awareness
Is it necessary?
5/ Classical conditioning and advertising
John B Watson (1878-1958)
Watson & Rayner (1920)
A loud noise elicit s a fear reaction
(crying and other fear-like responses)
Little Albert: conditioned to a white lab rat paired
with loud noise
When playing with rat experimenters would strike
a steel bar with a hammer behind Albert’s head
Little Albert began to show fear to the rat
(crying and crawling away)
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Treating Phobias
Mary Cover Jones (1924) student of Watsons
Used classical conditioning to reduce fear reactions.
Example: Peter, a toddler with a fear of rabbits
She used counterconditioning on Peter
Counterconditioning
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One CS is presented at the same time as another event, that elicits an
incompatible response
¾ Jones (1924) brought a rabbit (CS that elicits anxiety) into the same room
but far away from Peter while he was eating his cookies and milk snack (CS
that elicits good feelings)
¾ Jones did this each day and gradually brought the rabbit closer and closer
until there was no fear to the rabbit (eventually the rabbit was put into his
lap!)
¾
Treating Phobias
Systematic Desensitization (Joseph Wolpe,1958)
Start by getting person to be relaxed
Create hierarchy of fear eliciting stimuli
from least to most strong example of stimulus
Gradually (from least to most) pair each item of hierarchy with relaxation
without producing fear (because of deep relaxation)
combines counterconditioning, generalization, and extinction
e.g. Early on the hiearchy would consist of imagining events – slowly
Move to more threatening situations
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Treating Phobias
Example:
Patient with a fear of snakes
Start off imagining a snake
Look at pictures of snakes
Look at a toy snake
Handle a toy snake
Be in the room with a snake in the cage
..Eventually handling snake putting it around his/her neck!
Systematic desensitization
Davison (1968)
Subjects with intense fear of snakes
13-step test to assess their initial fear – involving progressively
More exposure to the snakes. Ranging from approaching a
Snake in a jar – to touching the snake for 30 seconds.
4 Groups:
1/ Systematic desensitization – progressively more aversive scenes involving
snakes – paired with relaxation exercises.
2/ Imagined disturbing childhood scenes – paired with relxation
3/ Imagined snakes as in 1/ but no relaxation
4/ No treatment: control group
Systematic desensitization group only group to show significant
Improvement.
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Systematic desensitization
Paul (1969) conducted a study with students that had severe anxieties about
public speaking
Had 3 treatment groups:
1/ Systematic desensitization group
2/ Psychotherapy group
3/ No treatment control group
Assessment 2 years later:
85% in the systematic desensitization group showed significant
improvement compared to pre-treatment levels
50% showed improvement in the psychotherapy group
Only 22 % in untreated control group
Effectiveness of systematic desensitization varies according to phobia
But.. one of the more successful treatment options for some phobias.
Flooding
Drop patients in at the deep end!
Expose them to fear provoking stimulus at full intensity.
Eventually they should start to extinguish their fear.
But this is extremely stressful.
Rothbaum (1995) used virtual reality technology to provide exposure
to the feared stimulus
Used VR to present subjects with fear of heights with realistic scenes
involving heights:
walking on foot bridges, outdoor balconies, riding up a glass elevator
Marked reduction in fear of heights – equivalent to actual flooding using
real heights.
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Counteracting Conditioned Taste Aversion
Broberg & Bernstein (1987)
Children undergoing chemotherapy would develop
taste aversions to the meal they had that day.
Gave the children a distinctive-flavored Lifesaver candy (CS)
between their evening meal and the chemo session (US) and
found that 12 of 15 children ate the food at the meal again later
On another occasion the same children were not given the
Lifesaver candy between the evening meal and chemotherapy,
and they found that only 6 of the 15 children would eat that meal
again
Aversion Therapy
Pair the problem behavior with an aversive stimulus
As an association forms the attractiveness of the problem
behavior is reduced
Example: Raymond (1964)
Used aversion therapy to help a 14 year old boy stop smoking
Gave injection of apomorphine
Then told to start smoking
11 minutes later became naseated and vomited.
4 days later came for treatment – reported felt nauseated when he tried
to light one
Two months later – felt nauseated when offered a cigarette
No longer smoked 1 year after treatment
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Another example
Tiffany et al., (1986)
Used smoking itself as the aversive stimulus to give up
smoking.
Smokers asked to smoke rapidly and inhale deeply every 6
seconds – continue smoking for 3 minutes or until they felt
unable to continue.
Rapid smoking led to nausea.
6 months treatment: 59% patients no longer smoked
compared to control groups
Other studies did not work so well
Tried pairing smoking or alcohol with shock – with
little success.
Another problem – even though treatment may be
successful in laboratory, patients often relapsed when
they went home.
Why might these methods not have succeeded as well
as they might?
Biological preparedness
Discrimination
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Other approaches
Psychodynamic (Freudian)
Cognitive-Behavioral therapy
Therapists focus on peoples cognitions as well as their behaviors
e.g. fear of public speaking may be associated with ‘irrational’
cognitions – assumption of ridicule, catastrophisation etc.
Therapy could be a combination of confronting those ‘irrational thoughts’
and behavioral modification to reduce fear.
Pharmacological
e.g. administration of anxiolytics or antidepressants
(beta blockers, benzodiazapenes, SSRIs)
Classical conditioning and advertising
Smith and Engel (1968)
Showed 120 subjects a picture of an automobile.
For half the subjects – photograph only showed the car
Others – car was paired with attractive female model
Subjects in 2nd group – rated car as better along a
number of dimensions and also more expensive (as
well as less safe).
Subjects denied that model influenced their judgment
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Classical conditioning and advertising
Gorn (1982)
Colleges students split into two groups.
One group listened to “popular” favorable music from Grease!!!
Another group listened to less favourable classical Indian music
While listening, students viewed slide showing beige or blue
Afterwards, students allowed to select pen
Grease Group: 79% chose pen of same color
Indian Group: 70% chose pen of different color from one they had seen on slide
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